Mustafi, 24, has won 12 caps for Germany after establishing himself as a regular for his La Liga side since his transfer from Sampdoria in 2014.

The former Everton academy graduate featured for the World Cup winners at Euro 2016 and scored in the opening match against Ukraine, which Germany won 2-0.

The Gunners are also looking likely to land Deportivo La Coruna striker Lucas Perez, after they triggered his £17.1million release clause.

The two new imminent signings will cost combined fees of close to £52million and will be a huge relief to Arsenal fans, who have been frustrated that their club have begun the season poorly, with a team weakened by injury and lack of fitness.

Manager Arsene Wenger has also been heavily criticised for his caution in a transfer market marked by inflated fees this summer, in the wake of the mammoth new Premier League TV deal.